JP2021009936A - Resin composition for underfill, and electronic component device and method for manufacturing the same - Google Patents

Abstract

To provide: a resin composition for underfill, excellent in low dielectric characteristics of a cured product; and an electronic component device in which the resin composition for underfill is used and a method for manufacturing the same.SOLUTION: A resin composition for underfill contains an epoxy resin, a curing agent and an inorganic filler. The curing agent comprises an acid anhydride-based curing agent, and a cured product has a relative permittivity of 3.5 or less and a dielectric loss tangent of 0.0100 or less.SELECTED DRAWING: None

Description

The present disclosure relates to a resin composition for underfilling, an electronic component device, and a method for manufacturing the same.

Conventionally, as a sealing material for sealing a semiconductor element such as a transistor and an IC (Integrated Circuit), a resin is mainly used from the viewpoints of productivity, cost and the like. Among them, epoxy resins having an excellent balance of various properties required for a sealing material such as workability, moldability, electrical properties, moisture resistance, heat resistance, mechanical properties, and adhesiveness to insert products are widely used. ing.

In recent years, with the miniaturization and thinning of electronic component devices in which semiconductor elements are sealed, so-called bare chip mounting, in which bare chips are mounted directly on a wiring board, has become mainstream. Examples of the electronic component device by mounting the bare chip include COB (Chip on Board), COG (Chip on Glass), TCP (Tape Carrier Package) and the like. In these electronic component devices, a liquid resin composition is widely used as a sealing material.

Further, an electronic component device (flip chip) in which a semiconductor element is directly bump-connected on a wiring board (hereinafter, also simply referred to as "board") having a ceramic, glass epoxy resin, glassimide resin, polyimide film or the like as a substrate. In, a sealing material called an underfill material is used to fill a gap between a bump-connected semiconductor element and a wiring board. The resin composition used as the underfill material plays an important role in protecting electronic components from temperature and humidity and mechanical external forces.

As an underfill material, for example, Patent Document 1 describes an epoxy resin, an amine-based curing agent, a filler, a core-shell rubber, and a reactive diluent, which are excellent in injectability, and have fillet cracks and growth, and voids. Suppressed semiconductor resin encapsulants have been reported. Further, Patent Document 2 contains a liquid epoxy resin, an amine-based curing agent, an acrylic resin, and an inorganic filler, has high reliability due to low thermal expansion and low elastic modulus, and has a filling property in a narrow gap. A liquid encapsulating resin composition excellent in the above has been reported.

Japanese Unexamined Patent Publication No. 2012-162585 Japanese Unexamined Patent Publication No. 2013-256547

In the information and communication field, radio waves are becoming higher in frequency as the number of channels increases and the amount of information transmitted increases. Currently, studies on 5th generation mobile communication systems are underway worldwide, and it is predicted that the mainstream of wireless communication will be communication in the high frequency band in the future.

The amount of transmission loss caused by the thermal conversion of radio waves transmitted for communication in a dielectric is expressed as the product of the square root of frequency and relative permittivity and the dielectric loss tangent. That is, since the transmission signal is easily converted into heat in proportion to the frequency, the material of the communication member is required to have low dielectric properties in the high frequency band in order to suppress the transmission loss.

However, so far, no knowledge has been reported regarding an underfill material having excellent low dielectric properties, which can be applied to communication in a high frequency band.

In view of the above circumstances, it is an object of the present disclosure to provide an underfill resin composition having excellent low dielectric properties of a cured product, an electronic component device using the underfill resin composition, and a method for manufacturing the same. ..

Specific means for achieving the above-mentioned problems are as follows.
<1> An epoxy resin, a curing agent, and an inorganic filler are contained, the curing agent contains an acid anhydride-based curing agent, the relative permittivity of the cured product is 3.5 or less, and the dielectric loss tangent is 0. A resin composition for underfill, which is 0100 or less.
<2> The resin composition for underfill according to <1>, wherein the content of the acid anhydride-based curing agent with respect to the total amount of the curing agent is 70% by mass or more.
<3> The underfill according to <1> or <2>, wherein the curing agent does not contain an amine-based curing agent, or the content of the amine-based curing agent is less than 30% by mass with respect to the total amount of the curing agent. Resin composition for.
<4> The curing agent does not contain an amine-based curing agent and a phenol-based curing agent, or the content of the amine-based curing agent and the phenol-based curing agent is less than 30% by mass in total with respect to the total amount of the curing agent. The resin composition for underfill according to any one of 1> to <3>.
<5> The resin composition for underfill according to any one of <1> to <4>, wherein the content of the inorganic filler is 50% by mass or more.
<6> The resin composition for underfill according to any one of <1> to <5>, which is a capillary underfill material.
<7> A substrate having a circuit layer and
Electronic components placed on the substrate and electrically connected to the circuit layer
The cured product of the resin composition for underfill according to any one of <1> to <6> arranged in the gap between the substrate and the electronic component.
Electronic component device equipped with.
<8> The electronic component device according to <7>, which is a communication member of a fifth generation mobile communication system.
<9> The underfill according to any one of <1> to <6>, the substrate having the circuit layer and the electronic components arranged on the substrate and electrically connected to the circuit layer. A method for manufacturing an electronic component device, which comprises a step of sealing using a resin composition for use.
<10> The manufacturing method according to <9>, wherein the electronic component device is a communication member of a fifth generation mobile communication system.

According to the present disclosure, a resin composition for underfill having excellent low dielectric properties of a cured product, an electronic component device using the resin composition for underfill, and a method for manufacturing the same are provided.

Hereinafter, embodiments for carrying out the present invention will be described in detail. However, the present invention is not limited to the following embodiments. In the following embodiments, the components (including element steps and the like) are not essential unless otherwise specified. The same applies to the numerical values and their ranges, and does not limit the present invention.
In the present disclosure, the term "process" includes not only a process independent of other processes but also the process if the purpose of the process is achieved even if the process cannot be clearly distinguished from the other process. ..
The numerical range indicated by using "~" in the present disclosure includes the numerical values before and after "~" as the minimum value and the maximum value, respectively.
In the numerical range described stepwise in the present disclosure, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value of another numerical range described stepwise. .. Further, in the numerical range described in the present disclosure, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples.
In the present disclosure, each component may contain a plurality of applicable substances. When a plurality of substances corresponding to each component are present in the composition, the content rate or content of each component is the total content rate or content of the plurality of substances present in the composition unless otherwise specified. Means quantity.
In the present disclosure, a plurality of types of particles corresponding to each component may be contained. When a plurality of particles corresponding to each component are present in the composition, the particle size of each component means a value for a mixture of the plurality of particles present in the composition unless otherwise specified.
In the present disclosure, the term "layer" or "membrane" is used only in a part of the region in addition to the case where the layer or the membrane is formed in the entire region when the region in which the layer or the membrane exists is observed. The case where it is formed is also included.
In the present disclosure, the epoxy resin means a compound having an epoxy group in the molecule, and may be a monomer or a polymer.

<Resin composition for underfill>
The underfill resin composition (also referred to as an underfill material) of the present disclosure contains an epoxy resin, a curing agent, and an inorganic filler, and the curing agent contains an acid anhydride-based curing agent, and is a cured product. The specific dielectric constant of is 3.5 or less and the dielectric loss tangent is 0.0100 or less.

The underfill material of the present disclosure is excellent in low dielectric properties of the cured product. The reason for this is not always clear, but it can be thought of as follows. Conventionally, as a curing agent for an epoxy resin in an underfill material, an amine-based curing agent has been generally used from the viewpoint of adhesiveness to an adherend and the like. However, when an amine-based curing agent is used, it is considered difficult to obtain suitable low-dielectric properties due to the polarity of the amine. On the other hand, when the epoxy resin is cured using an acid anhydride-based curing agent, it is considered that the amount of polar groups in the cured product and its polarity can be suppressed as compared with the case where an amine-based curing agent is used. Further, when the epoxy resin is cured using the acid anhydride-based curing agent, as an estimation mechanism, the secondary hydroxyl group generated by the ring opening of the epoxy group of the epoxy resin is consumed by the acid anhydride-based curing agent. Therefore, it is considered that the amount of hydroxyl groups in the cured product is also reduced. As described above, it is considered that the low dielectric property of the cured product is improved by reducing the amount of polar groups in the cured product and its polarity. Further, in the resin composition containing the acid anhydride-based curing agent, a resin composition having a relative permittivity of 3.5 or less and a dielectric loss tangent of 0.0100 or less of the cured product is obtained to obtain low dielectric constant. It is considered that a cured product having excellent properties can be preferably obtained.

The underfill material is preferably liquid at room temperature. In the present disclosure, "normal temperature" means 25 ° C., and "liquid" means a substance showing fluidity and viscosity and having a viscosity of 0.0001 Pa · s to 100 Pa · s, which is a measure of viscosity. .. Further, "liquid" means that it is in a liquid state.

In the present disclosure, the viscosity is defined as a measured value when an EHD type rotational viscometer (for example, manufactured by Tokyo Keiki Co., Ltd.) is rotated at 25 ° C. for 1 minute and 10 times per minute (10 rpm). The above measured values are obtained for a liquid maintained at 25 ± 1 ° C. using an EHD type rotational viscometer equipped with a cone rotor having a cone angle of 3 ° and a cone radius of 14 mm.

The viscosity of the underfill material is not particularly limited. Above all, from the viewpoint of high fluidity, it is preferably 0.1 Pa · s to 100.0 Pa · s at 25 ° C., more preferably 0.1 Pa · s to 50.0 Pa · s, and 0.1 Pa · s. It is more preferably s to 30.0 Pa · s.

Further, as an index of ease of filling when filling the underfill material in a narrow gap of several tens of μm to several hundreds of μm in the vicinity of 100 ° C to 120 ° C, the viscosity of the underfill material at 110 ° C is 0.20 Pa. It is preferably s or less, and more preferably 0.15 Pa · s or less. The viscosity of the underfill material at 110 ° C. is measured by a rheometer AR2000 (for example, manufactured by TA Instrument, aluminum cone 40 mm, shear rate 32.5 / sec).

The underfill material has a fluctuation index [, which is the ratio of the viscosity at a rotation speed of 2.5 rotations / minute and the viscosity at a rotation speed of 10 rotations / minute measured at 25 ° C. using an E-type viscometer. (Viscosity at 2.5 rpm) / (Viscosity at 10 rpm)] is preferably 0.5 to 1.5, more preferably 0.8 to 1.2. When the fluctuation index is in the above range, the fillet forming property is further improved. The viscosity and fluctuation index of the underfill material can be set in a desired range by appropriately selecting the composition of the epoxy resin, the content of the inorganic filler, and the like.

The relative permittivity (Dk) when the underfill material is a cured product is 3.5 or less, preferably 3.4 or less, more preferably 3.3 or less, and 3.2 or less. Is more preferable.

The dielectric loss tangent (Df) when the underfill material is a cured product is 0.0100 or less, preferably 0.0090 or less, and more preferably 0.0080 or less.

The relative permittivity and the dielectric loss tangent are the relative permittivity and the dielectric loss tangent when the underfill material is cured at 150 ° C. for 2 hours. The relative permittivity and the dielectric loss tangent are measured as values at a frequency of 20 GHz using a cavity resonance measuring device. Specifically, the relative permittivity and the dielectric loss tangent can be determined by the method described in Examples.

The underfill material of the present disclosure contains an epoxy resin, a curing agent, and an inorganic filler, and may contain other components if necessary. Hereinafter, each component of the underfill material will be described in detail.

(Epoxy resin)
The underfill material of the present disclosure contains an epoxy resin. The type of epoxy resin is not particularly limited, and can be selected from those generally used as materials for underfill materials. One type of epoxy resin may be used alone, or two or more types may be used in combination.
Examples of the epoxy resin include novolak type epoxy resins such as phenol novolac type epoxy resin and cresol novolac type epoxy resin; bisphenol type epoxy resin such as bisphenol A type epoxy resin and bisphenol F type epoxy resin; N, N-diglycidyl aniline, N. , N-diglycidyl toluidine, diaminodiphenylmethane type glycidylamine, aminophenol type glycidylamine and other aromatic glycidylamine type epoxy resins; phenol aralkyl type epoxy resins having at least one of a phenylene skeleton or a biphenylene skeleton; Aralkyl type epoxy resin such as naphthol aralkyl type epoxy resin having at least one; hydroquinone type epoxy resin; biphenyl type epoxy resin; stillben type epoxy resin; triphenol methane type epoxy resin; triphenol propane type epoxy resin; alkyl modified triphenol methane Type epoxy resin; Triazine nucleus-containing epoxy resin; Dicyclopentadiene-modified phenol type epoxy resin; Naftor type epoxy resin; Naphthalene type epoxy resin; Vinyl cyclohexene dioxide, dicyclopentadiene oxide, alicyclic diepoxy-adipate and other aliquots Formula Epoxy Resins: Bifunctional aliphatic epoxy compounds having two epoxy groups in the molecule, such as alkylene glycol diglycidyl ether, poly (alkylene glycol) diglycidyl ether, and alkenylene glycol diglycidyl ether.

Among the above epoxy resins, an epoxy resin containing a structure in which a glycidyl structure or a glycidylamine structure is bonded to an aromatic ring is preferable from the viewpoint of improving heat resistance, mechanical properties and moisture resistance.

The epoxy resin may be liquid or solid at room temperature, and from the viewpoint of making the underfill material liquid at room temperature, it is preferable to select the epoxy resin so that the epoxy resin as a whole becomes liquid at room temperature. When an epoxy resin solid at room temperature is used, the content thereof is preferably 20% by mass or less of the total epoxy resin from the viewpoint of fluidity.

The epoxy equivalent of the epoxy resin is not particularly limited, and is preferably 60 g / eq to 500 g / eq from the viewpoint of balancing various properties such as low dielectric property, moldability, reflow resistance, and electrical reliability, and 70 g. It is more preferably / eq to 300 g / eq, and even more preferably 90 g / eq to 200 g / eq. The epoxy equivalent of the epoxy resin shall be a value measured by a method according to JIS K 7236: 2009.

When two or more kinds of epoxy resins are used, the two or more kinds of epoxy resins may be mixed in advance and then mixed with other components, or may be mixed with other components without being mixed in advance.

The content of the epoxy resin in the underfill material is not particularly limited. From the viewpoint of low dielectric properties, the content of the epoxy resin is preferably 60% by mass or less, more preferably 50% by mass or less, and further preferably 40% by mass or less of the entire underfill material. , 30% by mass or less is particularly preferable, and 25% by mass or less is extremely preferable. From the viewpoints of reactivity during curing, heat resistance and mechanical strength after curing, and fluidity during sealing, the epoxy resin content is preferably 5% by mass or more of the entire underfill material. It is more preferably mass% or more, and further preferably 15 mass% or more.

The purity of the epoxy resin is preferably high. Specifically, it is preferable that the amount of hydrolyzable chlorine is small because it is related to the corrosion of aluminum wiring on an element such as an IC. From the viewpoint of obtaining an underfill material having excellent moisture resistance, the amount of hydrolyzable chlorine in the entire epoxy resin is preferably 500 ppm or less, for example.

Here, the amount of hydrolyzable chlorine was determined by dissolving 1 g of the epoxy resin of the sample in 30 ml of dioxane, adding 5 ml of a 1N-KOH (potassium hydroxide) methanol solution, refluxing for 30 minutes, and then potentiometric titration. It is a measure of value.

(Hardener)
The underfill material of the present disclosure contains a curing agent. The curing agent includes an acid anhydride-based curing agent.

The type of acid anhydride-based curing agent is not particularly limited. Examples of the acid anhydride-based curing agent include phthalic anhydride, maleic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, and methylbutenyltetrahydrophthalic anhydride. Hymic anhydride, methyl hymic anhydride, chlorendic anhydride, succinic anhydride, trimellitic anhydride, pyromellitic anhydride, trialkyltetrahydrophthalic anhydride maleic anhydride, benzophenone tetracarboxylic dianhydride, methyl hydride Examples thereof include nadic acid anhydride and dodecenyl succinic anhydride. The acid anhydride-based curing agent may be used alone or in combination of two or more.

Among them, from the viewpoint of fluidity, low viscosity, etc., the phthalic anhydride-based curing agent is preferably a phthalic anhydride-based curing agent, more preferably phthalic anhydride substituted with a hydrocarbon group, and methylbutenyl. It is more preferable to contain at least one selected from the group consisting of tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, and methylhexahydrophthalic anhydride.

From the viewpoint of making the underfill material liquid at room temperature, the acid anhydride-based curing agent is preferably liquid at room temperature (25 ° C.).

The equivalent ratio of the acid anhydride groups in the acid anhydride-based curing agent to the epoxy groups in the epoxy resin (equivalent number of acid anhydride groups / equivalent number of epoxy groups) keeps each unreacted component low and From the viewpoint of sufficiently advancing the curing reaction, it is preferably set in the range of 0.7 to 1.3, more preferably set in the range of 0.8 to 1.2, and 0.9 to 1. It is more preferable to set it in the range of 1.

The curing agent may contain other curing agents such as an amine-based curing agent and a phenol-based curing agent in addition to the acid anhydride-based curing agent, but from the viewpoint of low dielectric properties, the curing agent is an amine-based curing agent. It is preferable that the content of the amine-based curing agent is less than 30% by mass based on the total amount of the curing agent, and the curing agent does not contain the amine-based curing agent or the content of the amine-based curing agent is the total amount of the curing agent. It is more preferable that the amount of the curing agent is less than 20% by mass, and it is more preferable that the curing agent does not contain an amine-based curing agent or the content of the amine-based curing agent is less than 10% by mass based on the total amount of the curing agent. It is particularly preferable that the curing agent does not contain an amine-based curing agent or the content of the amine-based curing agent is less than 5% by mass based on the total amount of the curing agent.

Further, from the viewpoint of low dielectric property and heat resistance, it is preferable that the curing agent does not contain a phenol-based curing agent or the content of the phenol-based curing agent is less than 30% by mass based on the total amount of the curing agent. It is more preferable that it does not contain a phenolic curing agent or the content of the phenolic curing agent is less than 20% by mass based on the total amount of the curing agent, and the curing agent does not contain a phenolic curing agent or contains a phenolic curing agent. The ratio is more preferably less than 10% by mass based on the total amount of the curing agent, and the curing agent does not contain a phenolic curing agent or the content of the phenolic curing agent is less than 5% by mass based on the total amount of the curing agent. Is particularly preferred.

From the viewpoint of low dielectric properties and heat resistance, the curing agent does not contain amine-based curing agent and phenol-based curing agent, or the content of amine-based curing agent and phenol-based curing agent is less than 30% by mass in total with respect to the total amount of curing agent. The curing agent does not contain an amine-based curing agent and a phenol-based curing agent, or the content of the amine-based curing agent and the phenol-based curing agent is less than 20% by mass in total with respect to the total amount of the curing agent. More preferably, the curing agent does not contain an amine-based curing agent and a phenol-based curing agent, or the content of the amine-based curing agent and the phenol-based curing agent is less than 10% by mass in total with respect to the total amount of the curing agent. It is particularly preferable that the curing agent does not contain an amine-based curing agent and a phenol-based curing agent, or the content of the amine-based curing agent and the phenol-based curing agent is less than 5% by mass in total with respect to the total amount of the curing agent.

From the viewpoint of low dielectric properties, the content of the acid anhydride-based curing agent with respect to the total amount of the curing agent is preferably 70% by mass or more, more preferably 80% by mass or more, and preferably 90% by mass or more. It is more preferably 95% by mass or more, and particularly preferably 95% by mass or more.

When an amine-based curing agent is used in combination, the type of the amine-based curing agent is not particularly limited, and is preferably a compound having an aromatic ring (also referred to as an aromatic amine compound), which is an aromatic amine compound that is liquid at room temperature. It is more preferable that the aromatic amine compound is liquid at room temperature and has two amino groups in one molecule. Examples of the aromatic amine compound liquid at room temperature include diaminodiphenylmethane and diethyltoluenediamine. One type of amine-based curing agent may be used alone, or two or more types may be used in combination.

When a phenolic curing agent is used in combination, the type of the phenolic curing agent is not particularly limited, and for example, a phenol compound (for example, phenol, cresol, xylenol, resorcin, catechol, bisphenol A and bisphenol F) and a naphthol compound (for example, bisphenol F) At least one selected from the group consisting of α-naphthol, β-naphthol and dihydroxynaphthalene) and aldehyde compounds (eg, formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde and salicylaldehyde) are condensed or co-condensed under an acidic catalyst. Examples thereof include novolak resin obtained by condensation; phenol / aralkyl resin; biphenyl / aralkyl resin; and naphthol / aralkyl resin. One type of phenolic curing agent may be used alone, or two or more types may be used in combination.

From the viewpoint of making the underfill material liquid at room temperature, it is preferable to select the curing agent so that the curing agent as a whole becomes liquid at room temperature. That is, when the underfill material contains only one kind of curing agent, it is preferable that the curing agent is liquid at room temperature. In the case of a combination of two or more types of curing agents, all of the two or more types of curing agents may be liquid at room temperature, some of them are solid curing agents at room temperature, and two or more types of curing agents are mixed. It may be a combination that becomes liquid at room temperature when it is used.
When a curing agent solid at room temperature is used as the curing agent, the content thereof is preferably 20% by mass or less of the entire curing agent from the viewpoint of fluidity.

Functional groups that react with epoxy groups in the curing agent with respect to the epoxy groups in the epoxy resin (for example, acid anhydride groups in the acid anhydride-based curing agent, active hydrogen groups in the amine-based curing agent, and phenol-based curing agents The equivalent ratio (the number of functional groups in the curing agent / the number of equivalents of the epoxy groups in the epoxy resin) of (hydroxyl group) is 0. From the viewpoint of suppressing each unreacted component to a small extent and sufficiently advancing the curing reaction. It is preferably set in the range of 7 to 1.3, more preferably in the range of 0.8 to 1.2, and even more preferably in the range of 0.9 to 1.1. ..

(Inorganic filler)
The underfill material of the present disclosure contains an inorganic filler.
The type of inorganic filler is not particularly limited. Specifically, as the inorganic filler, silica such as molten silica and crystalline silica, calcium carbonate, clay, alumina, silicon nitride, silicon carbide, boron nitride, calcium silicate, potassium titanate, aluminum nitride, beryllia, zirconia, zircone, Examples thereof include powders of fosterite, steatite, spinel, mulite, titania and the like, beads obtained by spheroidizing the powder, glass fibers and the like. A flame-retardant filler may be used as the inorganic filler. Examples of the inorganic filler having a flame-retardant effect include aluminum hydroxide, magnesium hydroxide, zinc borate, zinc molybdate and the like. As the inorganic filler, one type may be used alone or two or more types may be used in combination.

The particle shape of the inorganic filler is not particularly limited, and may be amorphous or spherical. From the viewpoint of fluidity and permeability of the underfill material into the fine gaps, the particle shape of the inorganic filler is preferably spherical. As the inorganic filler, for example, spherical silica is preferable, and spherical fused silica is more preferable.

The average particle size of the inorganic filler is not particularly limited, and is preferably 0.1 μm to 10 μm, more preferably 0.3 μm to 5 μm, for example. When the average particle size of the inorganic filler is 0.1 μm or more, the dispersibility in resin components (epoxy resin, curing agent, etc.) tends to be improved, and the flow characteristics of the underfill material tend to be further improved, and 10 μm or less. If this is the case, it becomes easier to suppress the sedimentation of the inorganic filler, and the permeability and fluidity into the fine gaps are improved, so that the generation of voids or unfilled portions tends to be further suppressed.

In the present disclosure, the average particle size of the inorganic filler means the volume average particle size. Specifically, it means the particle diameter (d50) when the accumulation from the small diameter side is 50% in the volume-based particle size distribution curve obtained by the laser diffraction / scattering method.

The maximum particle size of the inorganic filler is not particularly limited, and can be set according to the size of the gap to which the underfill material is applied. From the viewpoint of filling properties into the fine gaps, the maximum particle size of the inorganic filler is preferably 50 μm or less, more preferably 40 μm or less, and further preferably 30 μm or less.
The maximum particle size of the inorganic filler is, for example, the maximum of the major diameters of 100 randomly selected inorganic fillers in an image of a flaky sample of an underfill material or a cured product thereof taken with a scanning electron microscope. It can be measured as a value.

The content of the inorganic filler in the underfill material is not particularly limited, and for example, it is preferably 20% by mass to 90% by mass, more preferably 30% by mass to 80% by mass of the entire underfill material. It is more preferably 40% by mass to 75% by mass, particularly preferably 50% by mass to 75% by mass, and extremely preferably 60% by mass to 75% by mass.
When the content of the inorganic filler is 20% by mass or more of the entire underfill material, the coefficient of thermal expansion of the cured product tends to decrease, and when it is 90% by mass or less, the viscosity of the underfill material is maintained low. The fluidity, permeability and dispensability tend to be well maintained.

Further, from the viewpoint of further improving the low dielectric property, the content of the inorganic filler is preferably 50% by mass or more, more preferably 55% by mass or more, and 60% by mass or more of the entire underfill material. Is more preferable, 63% by mass or more is particularly preferable, and 65% by mass or more is extremely preferable. When the content of the inorganic filler is 50% by mass or more of the entire underfill material, the amount of polar groups in the underfill material is reduced, and as a result, it is considered that excellent low dielectric properties can be easily obtained.

(Other ingredients)
Underfill materials include coupling agents, curing accelerators, ion trapping agents, antioxidants, organic solvents, mold release agents, colorants, rubber particles, leveling agents, defoaming agents, etc., as additives other than the above-mentioned components. May be included as needed.

-Coupling agent-
The underfill material of the present disclosure may contain a coupling agent.
The coupling agent plays a role of strengthening the adhesiveness between the resin component in the underfill material and the inorganic filler, or between the resin component and the constituent members of the electronic component device. The type of the coupling agent is not particularly limited, and can be selected from those generally used as components of the underfill material. Specifically, silane compounds such as aminosilane, epoxysilane, mercaptosilane, alkylsilane, ureidosilane, and vinylsilane having one or more selected from the group consisting of primary amino groups, secondary amino groups, and tertiary amino groups. , Titanium compounds, aluminum chelate, aluminum / silane compounds and the like. Among these, from the viewpoint of filling property, a silane compound is preferable, and an epoxy silane is more preferable.

When the underfill material contains a coupling agent, its content is not particularly limited. From the viewpoint of strengthening the interfacial adhesion between the resin component and the inorganic filler and the interfacial adhesion between the resin component and the constituent members of the electronic component device, and improving the filling property, the content of the coupling agent is, for example, It is preferably 0.05% by mass to 10% by mass, more preferably 0.2% by mass to 5% by mass, and further preferably 0.4% by mass to 1% by mass of the entire underfill material. preferable.

-Curing accelerator-
The underfill material of the present disclosure may contain a curing accelerator. The type of the curing accelerator is not particularly limited, and a known curing accelerator can be used.
Specifically, 1,8-diaza-bicyclo [5.4.0] undecene-7, 1,5-diaza-bicyclo [4.3.0] nonen, 5,6-dibutylamino-1,8- Cycloamidin compounds such as diaza-bicyclo [5.4.0] undecene-7; maleic anhydride, 1,4-benzoquinone, 2,5-turquinone, 1,4-naphthoquinone, 2,3-dimethyl as cycloamidin compounds Kinone compounds such as benzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, phenyl-1,4-benzoquinone, diazo Compounds with intramolecular polarization formed by adding a compound having a π bond such as phenylmethane and phenol resin; tertiary amine compounds such as benzyldimethylamine, triethanolamine, dimethylaminoethanol and tris (dimethylaminomethyl) phenol; Derivatives of tertiary amine compounds; 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2 -Imidazole compounds such as phenyl-4,5-dihydroxymethylimidazole; derivatives of imidazole compounds; organic phosphine compounds such as tributylphosphine, methyldiphenylphosphine, triphenylphosphine, tris (4-methylphenyl) phosphine, diphenylphosphine, phenylphosphine, etc. A phosphorus compound having intramolecular polarization obtained by adding a compound having a π bond such as maleic anhydride, the above-mentioned quinone compound, diazophenylmethane, or phenol resin to an organic phosphine compound; tetraphenylphosphonium tetraphenylborate, triphenylphosphonium tetra Tetraphenylborate salts such as phenylborate, 2-ethyl-4-methylimidazolium tetraphenylborate, N-methylmorpholinium tetraphenylborate; derivatives of tetraphenylborate salt; triphenylphosphine-triphenylborane complex, morpholin- Examples thereof include a tetraphenylborane complex such as a triphenylborane complex. As the curing accelerator, one type may be used alone, or two or more types may be used in combination.

When the underfill material contains a curing accelerator, the content of the curing accelerator is preferably 0.1% by mass to 8% by mass with respect to the total amount of the epoxy resin and the curing agent.

-Ion trap agent-
The underfill material of the present disclosure may contain an ion trap agent.
The ion trap agent that can be used in the present disclosure is not particularly limited as long as it is an ion trap agent that is generally used in an underfill material used for manufacturing an electronic component device. Examples of the ion trapping agent include compounds represented by the following general formula (VI-1) or the following general formula (VI-2).

Mg _1-a Al _a (OH) ₂ (CO ₃ ) _{a / 2}・ uH ₂ O ・ ・ ・ General formula (VI-1)
(In the general formula (VI-1), a is 0 <a≤0.5 and u is a positive number.)
BiO _b (OH) _c (NO ₃ ) _d ... General formula (VI-2)
(In the general formula (VI-2), b is 0.9 ≦ b ≦ 1.1, c is 0.6 ≦ c ≦ 0.8, and d is 0.2 ≦ d ≦ 0.4.)

Ion trap agents are available as commercial products. As a compound represented by the general formula (VI-1), for example, "DHT-4A" (manufactured by Kyowa Chemical Industry Co., Ltd., trade name) is available as a commercially available product. Further, as a compound represented by the general formula (VI-2), for example, "IXE500" (manufactured by Toagosei Co., Ltd., trade name) is available as a commercially available product.

Examples of ion trapping agents other than the above include hydrous oxides of elements selected from magnesium, aluminum, titanium, zirconium, antimony and the like.
One type of ion trapping agent may be used alone, or two or more types may be used in combination.

When the underfill material contains an ion trapping agent, the content of the ion trapping agent is preferably 1 part by mass or more with respect to 100 parts by mass of the epoxy resin from the viewpoint of realizing sufficient moisture resistance reliability. From the viewpoint of fully exerting the effects of the other components, the content of the ion trap agent is preferably 15 parts by mass or less with respect to 100 parts by mass of the epoxy resin, and is preferably 1 part by mass to 10 parts by mass. Is more preferable, and 2 parts by mass to 5 parts by mass is further preferable.

The average particle size of the ion trap agent is preferably 0.1 μm to 3.0 μm, and the maximum particle size is preferably 10 μm or less. The average particle size of the ion trap agent can be measured in the same manner as in the case of the inorganic filler.

-Antioxidant-
The underfill material of the present disclosure may contain an antioxidant. As the antioxidant, conventionally known ones can be used.
Examples of the phenol compound antioxidant include 2,6-di-t-butyl-4-methylphenol and n-octadecyl-3- (3,5) as compounds having at least one alkyl group at the ortho position of the phenol nucleus. -Di-t-butyl-4-hydroxyphenyl) propionate, 2,2'-methylenebis- (4-methyl-6-t-butylphenol), 3,9-bis [2- [3- (3-t-butyl) -4-Hydroxy-5-methylphenyl) propionyloxy] -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane, 4,4'-butylidenebis- (6-- t-Butyl-3-methylphenol), 4,4'-thiobis (6-t-butyl-3-methylphenol), tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) ) Propionate] methane, 2,2-thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], N, N'-hexamethylenebis [3- (3,5) -Di-t-Butyl-4-hydroxyphenyl) propionamide], isooctyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, 1,3,5-trimethyl-2,4 6-Tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, 4,6-bis (dodecylthiomethyl) -o-cresol, bis [3,5-di-t-butyl-4- Hydroxybenzyl (ethoxy) phosphinate] calcium, 2,4-bis (octylthiomethyl) -6-methylphenol, 1,6-hexanediol-bis [3- (3,5-di-t-butyl-4-hydroxy) Phenyl) propionate], 6- [3- (3-t-butyl-4-hydroxy-5-methylphenyl) propoxy] -2,4,8,10-tetra-t-butyldibenz [d, f] [1, 3,2] Dioxaphosphepine, 2-t-butyl-6- (3-t-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenylacrylate, 2- [1- (2-hydroxy) -3,5-di-t-pentylphenyl) ethyl] -4,6-di-t-pentylphenyl acrylate, 2,2'-methylenebis- (4-ethyl-6-t-butylphenol), 2,6- Di-t-butyl-4-ethylphenol, 1,1,3-tris (2-methyl-4-hydroxy-5-t-butylphenyl) Tan, triethylene glycol-bis [3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionate], tris (3,5-di-t-butyl-4hydroxybenzyl) isocyanurate, diethyl [ [3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl] methyl] phosphonate, 2,5,7,8-tetramethyl-2- (4', 8', 12'-trimethyltridecyl ) Chroman-6-ol, 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -1,3,5-triazine and the like.
Examples of organic sulfur compound antioxidants include dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate, and pentaerythrityl. Tetrax (3-laurylthiopropionate), ditridecyl-3,3'-thiodipropionate, 2-mercaptobenzimidazole, 4,4'-thiobis (6-t-butyl-3-methylphenol), 2, 2-thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 4,6-bis (dodecylthiomethyl) -o-cresol, 2,4-bis (octyl) Thiomethyl) -6-methylphenol, 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -1,3,5-triazine and the like can be mentioned. ..
Examples of amine compound antioxidants include N, N'-diallyl-p-phenylenediamine, N, N'-di-sec-butyl-p-phenylenediamine, octylated diphenylamine, and 2,4-bis- (n-). Octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -1,3,5-triazine and the like can be mentioned.
Among the amine compound-based antioxidants, as dicyclohexylamine, trade name D-CHA-T manufactured by Shin Nihon Rika Co., Ltd. is available as a commercially available product, and its derivatives include dicyclohexylamine ammonium nitrite, N, N. Examples thereof include −di (3-methyl-cyclohexylamine) amine, N, N-di (2-methoxy-cyclohexylamine) amine, N, N-di (4-bromo-cyclohexylamine) amine and the like.
Examples of phosphorus compound antioxidants include trisnonylphenylphosphite, triphenylphosphite, bis [3,5-di-t-butyl-4-hydroxybenzyl (ethoxy) phosphinate] calcium, and tris (2,4-di). -T-butylphenyl) phosphite, 2-[[2,4,8,10-tetrakis (1,1-dimethylether) dibenzo [d, f] [1,3,2] dioxaphosfepin- 6-yl] Oxy] -N, N-bis [2-{[2,4,8,10-tetrakis (1,1-dimethylethyl) dibenzo [d, f] [1,3,2] dioxaphos Fepin-6-yl] oxy} -ethyl] etanamine, 6- [3- (3-t-butyl-4-hydroxy-5-methylphenyl) propoxy] -2,4,8,10-tetra-t- Butyldibenz [d, f] [1,3,2] dioxaphosphepine, diethyl [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl] methyl] phosphonate and the like can be mentioned.
One type of antioxidant may be used alone, or two or more types may be used in combination. As a specific example of the antioxidant, there are compounds containing at least one of a phosphorus atom, a sulfur atom and an amine in the same molecule in addition to the phenolic hydroxyl group, but these compounds may be mentioned in duplicate. is there.

When the underfill material contains an antioxidant, the content of the antioxidant is preferably 0.1% by mass to 10% by mass, more preferably 0.5% by mass or more, based on the entire epoxy resin. It is 5% by mass.

-Organic solvent-
The underfill material of the present disclosure may be blended with an organic solvent, if necessary, in order to reduce the viscosity. In particular, when a solid epoxy resin and a curing agent are used, it is preferable to add an organic solvent in order to obtain a liquid resin composition.
The organic solvent is not particularly limited, and alcohol-based solvents such as methyl alcohol, ethyl alcohol, propyl alcohol and butyl alcohol; ketone solvents such as acetone and methyl ethyl ketone; ethylene glycol ethyl ether, ethylene glycol methyl ether and ethylene glycol butyl ether, Glycol ether solvents such as propylene glycol methyl ether, dipropylene glycol methyl ether, propylene glycol ethyl ether and propylene glycol methyl ether acetate; lactone solvents such as γ-butyrolactone, δ-valerolactone and ε-caprolactone; dimethylacetamide, dimethyl Examples thereof include amide solvents such as formamide; aromatic solvents such as toluene and xylene, and one type may be used alone or two or more types may be used in combination. Among these, an organic solvent having a boiling point of 170 ° C. or higher is preferable from the viewpoint of avoiding the formation of bubbles due to rapid volatilization when the underfill material is cured.

The content of the volatile matter containing the organic solvent and the like is not particularly limited as long as it does not form bubbles when the underfill material is cured, and is preferably 5% by mass or less with respect to the entire underfill material. It is more preferably 1% by mass or less, and further preferably 0.1% by mass or less.
In the present disclosure, the volatile content of the underfill material is calculated based on the weight difference before and after heating the underfill material at 180 ° C. for 30 minutes.

-Release agent-
The underfill material of the present disclosure may contain a mold release agent. The type of release agent is not particularly limited, and a known release agent can be used. Specific examples thereof include higher fatty acids, carnauba wax and polyethylene wax. As the release agent, one type may be used alone, or two or more types may be used in combination.
When the underfill material contains a release agent, the content of the release agent is preferably 10% by mass or less with respect to the total amount of the epoxy resin and the curing agent, and from the viewpoint of exerting the effect. , 0.5% by mass or more is preferable.

-Colorant-
The underfill material of the present disclosure may contain a colorant such as a dye or carbon black. One type of colorant may be used alone, or two or more types may be used in combination.

When conductive particles such as carbon black are used as the colorant, the content of the conductive particles is preferably 1% by mass or less of particles having a particle diameter of 10 μm or more.
When the underfill material contains conductive particles, the content of the conductive particles is preferably 3% by mass or less, preferably 0.01% by mass to 1% by mass, based on the total amount of the epoxy resin and the curing agent. Is more preferable.

-Rubber particles-
The underfill material may contain rubber particles from the viewpoint of low thermal expansion of the cured product. One type of rubber particles may be used alone, or two or more types may be used in combination.
Examples of suitable rubber particles include rubber particles such as styrene-butadiene rubber (SBR), nitrile-butadiene rubber (NBR), butadiene rubber (BR), urethane rubber (UR), and acrylic rubber (AR). Among them, from the viewpoint of heat resistance and moisture resistance, rubber particles containing acrylic rubber are preferable, and core-shell type acrylic rubber particles are more preferable.

Further, as another example of suitable rubber particles, silicone rubber particles can be mentioned.
The silicone rubber particles include silicone rubber particles obtained by cross-linking linear polyorganosiloxanes such as polydimethylsiloxane, polymethylphenylsiloxane, and polydiphenylsiloxane; the surface of the silicone rubber particles coated with silicone resin, and emulsion polymerization. Examples thereof include core-shell polymer particles containing a core of solid silicone particles obtained by the above and a shell of an organic polymer such as an acrylic resin. The shape of these silicone rubber particles may be amorphous or spherical, and in order to keep the viscosity of the underfill material low, it is preferable to use spherical silicone rubber particles.
Commercially available silicone rubber particles are available from Toray Dow Corning Silicone Co., Ltd., Shin-Etsu Chemical Co., Ltd., and the like.

When the underfill material contains rubber particles, the average particle size of the rubber particles is preferably fine in order to uniformly modify the underfill material. The average particle size of the rubber particles is preferably in the range of 0.05 μm to 10 μm, and more preferably in the range of 0.1 μm to 5 μm. When the average particle size of the rubber particles is 0.05 μm or more, the dispersibility in the underfill material tends to be further improved. When the volume average particle diameter of the rubber particles is 10 μm or less, the effect of improving the stress reduction tends to be further improved, the permeability and fluidity into the fine gaps as the underfill material are improved, and voids and unfilling are formed. It tends to be difficult to invite.
The average particle size of the rubber particles is measured using the same method as for the inorganic filler.
When the underfill material contains rubber particles, the content of the rubber particles is preferably 3% by mass to 30% by mass, more preferably 5% by mass to 28% by mass, based on the total amount of the epoxy resin. It is more preferably 10% by mass to 25% by mass.

[Use of underfill material]
The underfill material can be applied to, for example, a semiconductor device equipped with an electronic component described later. In particular, the underfill material of the present disclosure is suitable as a capillary underfill material (CUF).
Further, in recent years, as the speed of a semiconductor element is increased, an interlayer insulating film having a low dielectric constant may be formed on the semiconductor element. The underfill material of the present disclosure can also be applied to a flip-chip connection type electronic component device equipped with a semiconductor element having such an interlayer insulating film.
In addition, the electronic component has excellent fluidity and filling property even for a flip chip connection in which the distance between the bump connection surface between the wiring board constituting the electronic component and the semiconductor element is, for example, 200 μm or less. There is a tendency to provide equipment.

[Preparation method of underfill material]
The underfill material is agitated, melted, mixed, for example, with epoxy resin, curing agent, and inorganic filler, and other components used as necessary, collectively or separately, with heat treatment if necessary. It can be obtained by dispersing or the like. The device for mixing, stirring, dispersing, etc. of these components is not particularly limited, and a masher equipped with a stirring device, a heating device, etc., a 3-roll mill, a ball mill, a planetary mixer, a bead mill, etc. Can be mentioned. An underfill material can be obtained by mixing the above components using these devices, kneading the components, and defoaming if necessary.

<Electronic component equipment>
The electronic component device of the present disclosure includes a substrate having a circuit layer, an electronic component arranged on the substrate and electrically connected to the circuit layer, and a book arranged in a gap between the substrate and the electronic component. A cured product of the disclosed underfill material is provided. The electronic component device of the present disclosure can be obtained by sealing the electronic component with the underfill material of the present disclosure.

Electronic component devices include lead frames, pre-wired tape carriers, rigid wiring boards, flexible wiring boards, glass, silicon wafers and other circuit layers, semiconductor elements, transistors, diodes, thyristors and other active elements, and capacitors. , An electronic component device obtained by mounting electronic components such as a resistor, a resistance array, a coil, and a switch, and sealing the necessary portion with the underfill material of the present disclosure.
In particular, an electronic component device in which a semiconductor element is flip-chip bonded by bump connection to a rigid wiring board, a flexible wiring board, or wiring formed on glass is mentioned as one of the objects to which the underfill material of the present disclosure can be applied. .. Specific examples include electronic component devices such as flip-chip BGA (Ball Grid Array), LGA (Land Grid Array), and COF (Chip On Film).

The underfill material of the present disclosure is useful as an underfill material for flip chips, which requires high reliability. In the field of flip chips to which the underfill material of the present disclosure is particularly preferably applied, not only when the bump material connecting the wiring board and the semiconductor element is a conventional lead-containing solder, but also when Sn-Ag-Cu It may also be a lead-free solder such as a system. The underfill material of the present disclosure tends to maintain good reliability even for flip chips in which bump connections are made using lead-free solder, which is physically fragile as compared with conventional lead solder. Further, when a chip scale package such as a wafer level CSP (Chip Size Package) is mounted on a substrate, the underfill material of the present disclosure tends to be applied to improve reliability.

Further, since the underfill material of the present disclosure is excellent in low dielectric property, it can be suitably applied to a communication member used for high frequency band communication such as a 5th generation mobile communication system.

<Manufacturing method of electronic component equipment>
In the method for manufacturing an electronic component device of the present disclosure, a substrate having a circuit layer and an electronic component arranged on the substrate and electrically connected to the circuit layer are sealed by using the underfill material of the present disclosure. It has a step of stopping.
The step of sealing the substrate having the circuit layer and the electronic component by using the underfill material of the present disclosure is not particularly limited. For example, a post-insertion method in which an underfill material is applied to a gap between an electronic component and a substrate by using a capillary phenomenon after connecting an electronic component and a substrate having a circuit layer, and then a curing reaction of the underfill material is performed. Further, when the underfill material of the present disclosure is applied to at least one surface of the substrate and the electronic component having the circuit layer first and then heat-pressed to connect the electronic component to the substrate, the connection and underfill of the electronic component and the substrate An example is a pre-coating method in which the curing reaction of the fill material is performed collectively.
Examples of the method for applying the underfill material include a casting method, a dispensing method, and a printing method.

The curing conditions of the underfill material are not particularly limited, and it is preferable to heat the underfill material at 80 ° C. to 165 ° C. for 1 minute to 150 minutes.

Hereinafter, the present invention will be described based on examples, but the present invention is not limited to the following examples.

[Preparation of underfill material]
Each component shown in Table 1 was blended in the amount shown in Table 1, kneaded and dispersed by a three-roll and vacuum grinder to prepare underfill materials of Examples and Comparative Examples. Details of each material shown in Table 1 are as follows. “-” In Table 1 indicates that the corresponding component is not blended.

-Epoxy resin 1: Liquid bifunctional epoxy resin obtained by epoxidizing bisphenol F (epoxy equivalent 160 g / eq)
-Epoxy resin 2: Liquid trifunctional epoxy resin obtained by epoxidizing aminophenol (epoxy equivalent 95 g / eq)
-Epoxy resin 3: Liquid bifunctional epoxy resin obtained by epoxidizing dihydroxynaphthalene (epoxy equivalent 143 g / eq)

-Curing agent 1: Methylbutenyltetrahydrophthalic anhydride (acid anhydride equivalent 117 g / eq)
-Curing agent 2: Methyltetrahydrophthalic anhydride (acid anhydride equivalent 83 g / eq)
-Curing agent 3: Methylhexahydrophthalic anhydride (acid anhydride equivalent 84 g / eq)
-Curing agent 4: Diethyl toluenediamine (active hydrogen equivalent 45 g / eq)
-Curing agent 5: 3,3'-diethyl-4,4'-diaminodiphenylmethane (active hydrogen equivalent 63 g / eq)
-Curing agent 6: 2,2'-diallyl bisphenol A (active hydrogen equivalent 70 g / eq)

-Curing accelerator 1: 2-ethyl-4-methylimidazole-Curing accelerator 2: 2-phenyl-4-methyl-5-hydroxymethylimidazole-Curing accelerator 3: 2-phenyl-4,5-dihydroxymethylimidazole

-Inorganic filler: silica
・ Colorant: Carbon black

[Evaluation]
Using the prepared underfill material, the viscosity, flow rate, relative permittivity, and dielectric loss tangent were evaluated by the following tests.

(1) Measurement of Viscosity at 25 ° C. An EHD type rotational viscometer (manufactured by Tokyo Keiki Co., Ltd.) was rotated at 25 ° C. for 1 minute 10 times per minute (10 rpm) to measure the viscosity. The measured values were obtained for a liquid kept at 25 ± 1 ° C. using an EHD type rotational viscometer equipped with a cone rotor having a cone angle of 3 ° and a cone radius of 14 mm.

(2) Flow rate 10 mg of the underfill material was injected into the gap between the support member (glass substrate) and the cover glass used as a substitute for the electronic component by the dispense method under the condition of 110 ° C. At this time, the time (sec) from the start of injection to the completion of filling was measured and evaluated as a guideline for the flow velocity shown in Table 1. The specifications of the evaluation sample are as follows.

-Glass substrate size: 76 mm x 26 mm Microslide glass (manufactured by Matsunami Glass Industry Co., Ltd.)
・ Cover glass size: 20 mm x 20 mm (manufactured by Matsunami Glass Industry Co., Ltd.)
-Gap between the substrate and the semiconductor element: 25 μm

(3) Relative Permittivity and Dielectric Dissipation Factor of Cured Product The prepared liquid sealing resin composition was cured at 150 ° C. for 2 hours to obtain a cured product. This cured product was cut into a size of 0.6 mm × 0.6 mm × 60 mm to prepare a measurement sample. Using this test piece, a cavity resonance measuring device (network analyzer: N5227A, manufactured by KEYSIGHT TECHNOLOGIES; resonator: CP561, Kanto Electronics Applied Development Co., Ltd.) was used to measure the relative permittivity and dielectric loss tangent at 20 GHz.

The results of each evaluation are shown in Table 1. In addition, "x" in the evaluation of the flow velocity indicates that it cannot be measured.

As shown in Table 1, all of the underfill materials of the examples had a relative permittivity of 3.5 or less and a dielectric loss tangent of 0.0100 or less. Further, the underfill material of the example had a viscosity suitable for the underfill material.

The underfill materials of these examples are excellent in low dielectric properties, and it is considered that they can be suitably used for applications in which low dielectric properties are desired.

Claims (10)

It contains an epoxy resin, a curing agent, and an inorganic filler, and the curing agent contains an acid anhydride-based curing agent, and the relative permittivity of the cured product is 3.5 or less and the dielectric loss tangent is 0.0100 or less. There is a resin composition for underfill. The resin composition for underfill according to claim 1, wherein the content of the acid anhydride-based curing agent with respect to the total amount of the curing agent is 70% by mass or more. The resin composition for underfill according to claim 1 or 2, wherein the curing agent does not contain an amine-based curing agent, or the content of the amine-based curing agent is less than 30% by mass based on the total amount of the curing agent. Stuff. Claims 1 to 1, wherein the curing agent does not contain an amine-based curing agent and a phenol-based curing agent, or the content of the amine-based curing agent and the phenol-based curing agent is less than 30% by mass in total with respect to the total amount of the curing agent. The resin composition for underfill according to any one of claims 3. The resin composition for underfill according to any one of claims 1 to 4, wherein the content of the inorganic filler is 50% by mass or more. The resin composition for underfill according to any one of claims 1 to 5, which is a capillary underfill material. A board with a circuit layer and
Electronic components placed on the substrate and electrically connected to the circuit layer
The cured product of the resin composition for underfill according to any one of claims 1 to 6, which is arranged in the gap between the substrate and the electronic component.
Electronic component device equipped with. The electronic component device according to claim 7, which is a communication member of a fifth-generation mobile communication system. The resin composition for underfill according to any one of claims 1 to 6, wherein a substrate having a circuit layer and an electronic component arranged on the substrate and electrically connected to the circuit layer are provided. A method for manufacturing an electronic component device, which comprises a step of sealing with an object. The manufacturing method according to claim 9, wherein the electronic component device is a communication member of a fifth generation mobile communication system.